The Purvanchal Range can be considered as the extension of Himalayas in the eastern part of India as the process of formation of this range is quite similar to that of Himalayas, although the range is not as high as the Himalayas. The Himalayas consist of three parallel ranges, the Greater Himalayas known as the Himadri, the Lesser Himalayas called the Himachal, and the Shivalik hills, which comprise the foothills. The northernmost Great, or Higher, Himalayas in ancient times, the Himadri , with crests generally above….
As you go above sea level or increase altitude or elevate, the temperature starts decreasing. Altitudes above meters are very cold and it snows more than rain. Thus more snow and low temperatures make sure the himalya stays snow covered. Snow is most common in high altitudes and high latitudes, particularly among the mountainous regions of the Northern and Southern Hemispheres.
Annually, snow covers as much as 46 million square kilometers about But wait! Our image contains peaks that max out around meters yet there is plenty of snow. Why is that? Coast Ranges, also called Pacific Coast Ranges, segment of the Pacific mountain system of western North America, consisting of a series of ranges in the United States running parallel to the Pacific coast for more than 1, miles 1, km from west-central Washington in the north to the Transverse Ranges of ….
British Columbia is the westernmost province of Canada, bordered by the Pacific Ocean. The province is almost four times the size of United Kingdom and larger than every U. England is 4. Swirled patterns of migmatite, Chelan, Washington. Height of outcrop is 6 feet. Somewhere between 80 and 90 million years ago, the huge Farallon Plate developed an enormous rupture that broke the seafloor into two independent oceanic plates.
We simply do not know why such a huge rift of the Farallon Plate occurred. Or, perhaps the huge plate became mechanically unstable as it continued to collide and subduct beneath North America. Whatever the case, when the Farallon Plate split it created two distinct oceanic plates separated by a new oceanic spreading center. The Farallon Plate ruptured between 80 and 90 million years ago, forming a new spreading center off the west coast of North America.
The part of the old Farallon Plate north of the spreading center was the Kula Plate. Even after the rupture, the Kula Plate continued its subduction beneath the Pacific Northwest. The new oceanic spreading ridge slowly migrated northward toward the Pacific Northwest. The new spreading ridge between the Kula and Farallon plates intersected the coast of North America in what is now northern California. In its early stages of development, the spreading ridge broke off pieces of offshore California.
These rocks of the ocean floor were sheared off and transported north along the edge of the continent. In the process, they were thoroughly fragmented, shattered and crushed into a disorganized jumble of rocks. Shuksan, Washington from Picture Lake. The chaotic rocks of Mt. Shuksan are typical of the fragmented, disorganized rocks of the Melange Belts. These rocks were originally sheared off from offshore California and transported north to Washington along the edge of the continent.
Photo by Wade B. To the north, the accreted Intermontane and Insular Belts had created a large embayment in the continental margin, and presented a south-facing coastline in the path of this northward-migrating melange complex.
The melange probably arrived here in more than one package. The earliest arrival was probably about 85 million years ago. In contrast to the accretion of the Intermontane and Insular Belts, the Melange Belts were not substantive enough to fill the trench and stall the subduction process. Instead, they were essentially scraped off the top of the subducting oceanic plate, and were thrust northward miles up and over the southern end of the Insular Belt.
The diagram above is a sketch map of the Columbia Embayment. The collision of the Intermontane and Insular Volcanic Islands in northern Washington left a great marine embayment to the south along the Washington-Oregon boundary. The Insular Belt in brown contains the remains of the Insular Volcanic Islands that collided with the Northwest about million years ago. The area shaded in red was intruded by magma from the Coast Range Arc.
The Melange Belt in dark blue collided between 85 and 75 million years ago. The southeastern extent of the Melange Belt buried by younger rocks is shown in the blue patterned area. Erosion wears down huge cliffs into smoother descents into the ocean. First you have this:. Then, after some time and sufficient rain, eroded material is deposited at the bottom of the cliffs, until you have this:. Given a few tens of millions of years, the process continues until the Andes themselves start several miles back from the beach, which is now a coastal plain.
Young mountains will rise directly out of the water. But beware, it takes a long time for a mountain to rise. By the time it has gotten to the height of the Andes, some millions of years have passed; plenty of time for a coastal plain to have developed.
The best way to slow down this erosion is to have a lack of water. But the west coast of South American from Lima, Peru south is about as dry a place as exists on Earth, and you can see on a map how much coastal plain has formed. Short answer: You can have cliffs like this, but they're not going to be as high as the Andes. Long Answer: You have several options for creating cliffs like this, but none of them are going to be as high as the Andes.
Let's zoom out and take a broader look:. In the pics on that page, you can see how it's just the western face of the cliffs that rise dramatically out of the water. The eastern side of the island gently slopes down. That's because the cliffs are a tilted block on a fault line. Another variation of fault block mountains is are horst and graben cliffs.
The scaled-up version of these is a rift valley with a narrow sea between them as kingledion points out, if you have enough time for an ocean to form, beaches will have formed. Whether or not you get this is dependent on what type of rock you have and how it erodes. It's also going to be about a mile high. The easiest way for you to not have beaches is to have something that gets rid of beaches. These processes exist. In other words, you want your waves to carry sand away faster than it can deposit.
This can be done with relatively swift offshore and nearshore currents and riptides. It helps if your mountains are made of relatively hard rock, like gneiss, that erodes slowly compared to how quickly the ocean washes sand away. The west coast of the US also has submarine canyons that give the sand a place to go as the current carries it away from the cliffs.
You might be disappointed about your mountains realistically being a mile high. Keep in mind the Velebit in Croatia are about a mile high.
Also, this is high enough to cause a pressure differential in winter that results in strong winds.
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